A novel synthesis of indeno[2',1': 5,6] pyrido[2,3- d ][1,2,4]triazolo[4,3- a ]pyrimidines

Reaction of 5-(4-chlorophenyl)-2-thioxo-2,3-dihydro-1H-indeno[2',1':5,6] pyrido[2,3-d]pyrimidine-4,6-dione with hydrazonoyl chlorides gave 1,2,4-triazolo[4,3-a]pyrimidine derivatives regioselectively in good yields. The structures of the newly synthesized compounds are established on the basis of chemical and spectroscopic evidence as well as their synthesis by alternative methods.     

3'-脱氧-3'-18F-氟代胸腺嘧啶核苷的合成研究

采用TRACERlab FXF-N自动化合成装置制备了肿瘤显像剂3'-脱氧-3'-18F-氟代胸腺嘧啶核苷(18F-FLT).以3-N-t-叔丁氧羰基-1-[5'-O-(4,4'-二甲氧基三苯甲基)-2'-脱氧-3'-O-(4-硝基苯磺酰基)-β-D-苏型-呋喃戊糖基]胸苷为前体,经过亲核氟化、盐酸水解两步反应及HPLC分离纯化制备18F-FLT,研究了不同因素对合成效率的影响.结果表明,总合成时间约55 min,未校正18F衰变情况下,放射化学产率约25%,放化纯度大于95%.     

5-氨基-1,4-苯并二恶烷盐酸盐的合成

以2,3-二羟基苯甲酸为原料,经酚羟基烷基化保护、羧酸叠氮化、Curtius重排、水解成盐四步反应以35%的总收率合成了5-氨基-1,4-苯并二恶烷盐酸盐,其结构经1H-NMR确认。由于合理的反应溶剂选择和反应温度控制,减少了副反应的发生、简化了工艺操作、降低了分离难度、提高了收率和产品纯度,使得该路线适合于工业化生产。     

萘并吡喃并[2,3-d]嘧啶-4(3H)-酮衍生物的合成与表征

通过氮杂Wittig反应合成了7种萘并吡喃并[2,3-d]嘧啶-4(3H)-酮衍生物。首先用2-萘酚、氰乙酸乙酯和芳醛通过Knoevenagl-Cope缩合得到2-氨基萘并吡喃(Ⅰ),(Ⅰ)再与三苯基膦反应得到膦亚胺中间体(Ⅱ)。(Ⅱ)与芳基异氰酸酯采用aza-Wittig反应得到碳二亚胺(Ⅲ)。(Ⅲ)再分别与胺、醇、酚反应合成了萘并吡喃并[2,3-d]嘧啶-4(3H)-酮Ⅳ(a-g)。目标化合物结构经1H-NMR、MS和IR进行了表征。试验考察了亲核试剂及反应条件对产品收率的影响。结果表明,亲核试剂空间位阻小反应速度较快,收率高;若有吸电子基团时,反应时间缩短。     

6，7-二氢-5H-环戊烷并[b]吡啶

6,7-二氢-5H-环戊烷并[b]吡啶主要用于药物、杀菌剂和抗菌剂的研究,也被广泛应用于制备植物保护剂和合成树脂、防老剂以及塑料制品等。目前因其被作为第四代抗生素头孢匹罗的侧链而成为研究者竞相开发的热点。6,7-二氢-5H-环戊烷并[b]吡啶有实用价值的合成方法主要有N-羟基邻苯二甲酰胺法、丙烯醛法和己二酸二乙酯法。丙烯醛法中6,7-二氢-5H-环戊烷并[b]吡啶的收率为87.4%,具有较好的开发前景。     

Microwave-assisted synthesis of [Cr]APO-5

The synthesis of the chromium-substituted aluminophosphate [Cr]APO-5 (AFI) using microwave irradiation was investigated systematically. The prepared materials were characterized by chemical analysis (ICP-AES), XRD, SEM, DR–UV–Vis spectroscopy, and sorption of different probe molecules, i.e., water, benzene, and nitrogen. Stable chromium incorporation into the AFI-framework can be achieved up to a chromium content of at least 3.2 mol% (5.6 wt.%). Besides the content of chromium and water, the nature and content of co-templates such as acetic acid or ethylene glycol in the gel for the microwave-assisted synthesis were varied. The concentration of the co-template is a key factor for successful [Cr]APO-5 synthesis. The microwave-assisted crystallization of [Cr]APO-5 was completed within 30 min whereas the conventional hydrothermal crystallization took at least 6 h for completion. Nevertheless, the yields and quality of [Cr]APO-5 obtained from hydrothermal and microwave-assisted synthesis are comparable.     

Regioselective synthesis of new 5-methyl-5H-pyrimido[4′,5′:4,5][1,3]thiazino [3,2-a]perimidines

A convenient and efficient regioselective synthesis of new pyrimido[4′,5′:4,5] [1,3]thiazino[3,2-a]perimidines is described through intermolecular heterocyclization of 2,4-dichloro-5-(chloromethyl)-6-methylpyrimidine and 1H-perimidine-2(3H)-thione in short reaction times under mild conditions.     

MANNICH reaction on 5-hydroxybenzo[b]thiophene

The reaction of 5-hydroxybenzo[b]thiophene 1 with formaldehyde and some primary and secondary amines has been investigated. Whereas secondary amines give always the corresponding 4-aminomethyl-derivatives 2 , the products with primary amines depend largely on the experimental conditions. The products, so obtained, have been characterized using micro- and spectral analyses.     

3-取代-6,7-二氢-5H-吡咯[2,1-c][1,2,4]三唑-5-羧酸甲酯的合成研究

以2-吡咯烷酮-5-羧酸甲酯为原料,经甲基化、取代和环合等反应,合成了16个目标化合物,其中13个为新化合物,其结构经~1HNMR和HR-MS确证。并且研究了环合反应条件,确定了环合反应的溶剂、催化剂及用量,即以氯苯为溶剂,2 mol%的醋酸为催化剂。该合成方法环合条件温和、操作简单,具有较强的通用性。     

Thermal stability of [B]ZSM-5 molecular sieve

The thermal stability of [BJZSM-5 (boronsilicalite) has been examined by IR, XRD,¹¹B MAS NMR and XPS techniques. [B]ZSM-5 and amorphous borosilicate were converted to α-cristobalite at high temperatures (=750C). However, Na-free amorphous borosilicate was not converted to a-cristobalite at 750C. Therefore, the presence of Na ions in [BJZSM-5 would determine whether this transition occurred or not. When the phase transition to α-cristobalite occurred, most of B atoms tetrahedrally coordinated were released from the ZSM-5 structure and migrated to the exterior surface as a boron compound having trigonal BO₃ units and oxidation states of 3.     

5-硝基-2-磺酰基苯并呋喃的合成研究

以5-硝基水杨醛为起始原料,经Horner-Wittig反应、水解得到5-硝基-2-羟基肉桂酸。该中间体分别与不同电性基团取代的苯亚磺酸钠,在Cu(OAc)_2和Ag OAc双金属体系作用下,经串联式反应得到2个5-硝基-2-磺酰基苯并呋喃化合物。其结构经~1H NMR、~(13)C NMR确证。     

N2O decomposition over [Fe]-ZSM-5 and Fe-HZSM-5 zeolites

The N₂O decomposition over an [Fe]-ZSM-5 and an Fe-HZSM-5 zeolite was studied. We found that framework incorporated iron species were much more active than Fe(III) introduced as framework charge countercations by ion exchange (TOF at 0.1 vol% N₂O:1.47 × 10^–4 at 280°C for [Fe]-ZSM-5 vs. 2.58 × 10^–4 at 468°C for Fe-HZSM-5). The higher activity of [Fe]-ZSM-5 was attributed to the uniqueness of framework iron species. Both [Fe]-ZSM-5 and Fe-HZSM-5 zeolites showed enhanced activity in the presence of excess oxygen. This is in sharp contrast to ruthenium exchanged zeolites which showed strong oxygen inhibiting effect on the rate of N₂O decomposition.     

Ring closure reaction of 5-hydroxy-pyrido[2,3-d]pyrimidine-2,4,7-triones to benzo[b]pyrimido[4,5-h]1,6-naphthyridine-1,3,6-triones

N-Substituted aminouracils ( 1 ) react with malonates by cyclocondensation to 5-hydroxy-pyrido[2,3-d]pyrimidine-2,4,7-triones ( 2 ), which give with triethylorthoformate and aniline 6-(phenylaminomethylene)-pyrido[2,3-d]pyrimidine-tetraone ( 3 ). Halogenation of 2a - d (with R² = Me) with phosphorylchloride leads to 5,7-dichloro-pyrido[2,3-d]pyrimidine-2,4-diones ( 4 ) by cleavage of the methyl group at N-8, whereas Vilsmeier reaction of 2 affords 5-chloro-6-formyl derivatives ( 6 ), which cyclize with arylamines to give benzo[b]pyrimido[4,5-h] 1,6-naphthyridines ( 9 ). Compounds 9 were obtained independently by amination of the tosylates 5 to the 5-arylamino compounds 8 , and Vilsmeier formylation to yield 9 .     

新环3-甲基-1-苯基-6-芳基偶氮-7-羟基双吡唑[5,1-c:3',4'-e]并-1,2,4-三嗪的合成

为进一步研发抑制细胞分裂周期磷酸酯酶CDC25B的抗肿瘤药物,以3-氨基-5-吡唑啉酮为原料,合成了8个新的标题化合物。通过元素分析、IR和1HNMR确证所得化合物的结构,并且确定其中有3个化合物对CDC25B具有较好的抑制活性。     

2,2’-双[4-(4-氨基苯氧基)苯基]丙烷的制备方法

介绍了以2,2’-双(4-羟基苯基)丙烷、对氯硝基苯,碱金属碳酸盐或碱金属氢氧化物为原料,在合适的溶剂中合成2,2’-双[4-(4-硝基苯氧基)苯基]丙烷,再经不同还原方法制备2,2’-双[4-(4-氨基苯氧基)苯基]丙烷。并从反应工艺条件、产品收率、产物纯度、是否适合规模化生产等方面阐述了制备2,2’-双[4-(4-氨基苯氧基)苯基]丙烷方法的优缺点。通过比较、分析指出了2,2’-双[4-(4-氨基苯氧基)苯基]丙烷的研究和发展方向。     

Pillar[5]arene-stabilized Plasmonic Nanoparticles as Selective SERS Sensors

We present here a simple procedure for the surface modification of plasmonic nanoparticles (NPs) with a cationic water-soluble ammonium pillar[5]arene (AP[5]A) in order to create selective surface-enhanced Raman scattering (SERS) spectroscopy based sensors. The strategy is based on a ligand exchange reaction between the AP[5]A and the stabilizing agent of the as-prepared plasmonic NPs. The approach could be applied to plasmonic nanoparticles either negatively charged, stabilized by citrate ions (Au spheres) or positively charged, stabilized by cetyltrimethylammonium bromide (Au and Au@Ag nanorods). The SERS performance of all systems was studied as a function of NP size and excitation laser line by using an analyte with no affinity towards the metal surface such as pyrene. The analytical enhancement factor (AEF) for the different systems was estimated between 0.55×10⁴ and 1.49×10⁵. Finally the synergistic effect of combining supramolecular chemistry and plasmonic NPs is demonstrated through SERS-based detection, in aqueous media, of molecules with no affinity towards a bare plasmonic substrate such as the contaminant pyrene or the biomolecule pyocyanin with nanomolar limit of detection.